To protect transmissions of sensitive data, an electronic device may encrypt the sensitive data before transmission. Once the transmission reaches the intended recipient, the intended recipient may decrypt the transmitted data to extract the sensitive data. In some cases, the electronic devices may request an external service to perform the encryption and decryption via a network. Encryption and decryption can be processor intensive, so offloading such tasks to an external service can allow the electronic devices to dedicate resources to other processes.
The external service may include devices that operate by encrypting or decrypting data using one or more keys. For example, a user device may transmit data to the external service for encryption, and the external service may then encrypt the data using a key and transmit the encrypted data to the user device. At a later time, the user device may transmit the encrypted data to the external service for decryption. The external service may identify the key used to encrypt the data and decrypt the encrypted data using the identified key. Thus, user data may be lost if the key becomes corrupted or otherwise unusable.